Spin spiral calculation

[zrqustc]

Dear VASP developers,

I did spin spiral calculations with q vector = (0,0,0) on LaNiO2 with PBE+U. It yields the magnetic moment  ± 0.648 μB and total energy: -53.49183176 eV. However when performing collinear calculations it yields: ± 0.975 μB and total energy: -53.53212588 eV. We expect the magnetic moment and total energy to be the same for both cases.
I also tested SCAN functional and got the same behavior.

Note: I used the interactive mode on NERSC-Perlmutter, so I do not attach any jobscript.

[ferenc_karsai]

I was redoing your calculations and got the same results.
I noticed that in one case you are using spin-orbit coupling and in the other not. So I would expect that the results differ.

[zrqustc]

Dear VASP developers,
I tested 3 calculations of LaNiO2 (with no spin orbit coupling):
1. Collinear with PBE+U(4eV)
2. Non collinear only with PBE+U(4eV), with the tag LNONCOLLINEAR = .True.
3. Non collinear PBE+U(4eV), with the tag LNONCOLLINEAR = .True., LSPIRAL=.TRUE., and QSPIRAL = 0.0 0.0 0.0

I’d expect to get the same energy and magnetic moment for all the calculations, but this is not the case for the spiral.
For each case, respectively, I’m getting:
1. Collinear: -53.5321254 eV, 0.975 μB
2. Non collinear only: -53.53228102 eV, 0.976 μB
3. Non collinear with spiral: -52.87347456 eV, 0.654 μB